mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, colorless to white (or various colors depending on impurities), vitreous (glassy) luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65.

Identified August 3, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, colorless to white (or various colors depending on impurities), vitreous (glassy) luster, trigonal crystal system, conchoidal fracture, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. It is a primary component of pegmatites and hydrothermal veins, crystallizing from silica-rich fluids over millions of years.

Uses & applications

Used in electronics (oscillators), glassmaking, abrasives, gemstones, and construction materials.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. Its piezoelectric properties make it essential for modern timekeeping and electronics.

Field identification & locations

Can be identified in the field by its characteristic hardness (scratches glass), lack of cleavage, and vitreous luster. Found worldwide in almost all rock types.